lib/3rdparty/freetype/src/autofit/aftypes.h

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  aftypes.h                                                              */
   4 /*                                                                         */
   5 /*    Auto-fitter types (specification only).                              */
   6 /*                                                                         */
   7 /*  Copyright 2003, 2004, 2005, 2006, 2007, 2008, 2009 by                  */
   8 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
   9 /*                                                                         */
  10 /*  This file is part of the FreeType project, and may only be used,       */
  11 /*  modified, and distributed under the terms of the FreeType project      */
  12 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
  13 /*  this file you indicate that you have read the license and              */
  14 /*  understand and accept it fully.                                        */
  15 /*                                                                         */
  16 /***************************************************************************/
  17
  18
  19   /*************************************************************************
  20    *
  21    *  The auto-fitter is a complete rewrite of the old auto-hinter.
  22    *  Its main feature is the ability to differentiate between different
  23    *  scripts in order to apply language-specific rules.
  24    *
  25    *  The code has also been compartmentized into several entities that
  26    *  should make algorithmic experimentation easier than with the old
  27    *  code.
  28    *
  29    *  Finally, we get rid of the Catharon license, since this code is
  30    *  released under the FreeType one.
  31    *
  32    *************************************************************************/
  33
  34
  35 #ifndef __AFTYPES_H__
  36 #define __AFTYPES_H__
  37
  38 #include <ft2build.h>
  39
  40 #include FT_FREETYPE_H
  41 #include FT_OUTLINE_H
  42 #include FT_INTERNAL_OBJECTS_H
  43 #include FT_INTERNAL_DEBUG_H
  44
  45
  46 FT_BEGIN_HEADER
  47
  48   /*************************************************************************/
  49   /*************************************************************************/
  50   /*****                                                               *****/
  51   /*****                    D E B U G G I N G                          *****/
  52   /*****                                                               *****/
  53   /*************************************************************************/
  54   /*************************************************************************/
  55
  56 #define xxAF_USE_WARPER  /* only define to use warp hinting */
  57 #define xxAF_DEBUG
  58
  59 #ifdef AF_DEBUG
  60
  61 #include FT_CONFIG_STANDARD_LIBRARY_H
  62
  63 #define AF_LOG( x )  do { if ( _af_debug ) printf x; } while ( 0 )
  64
  65 extern int    _af_debug;
  66 extern int    _af_debug_disable_horz_hints;
  67 extern int    _af_debug_disable_vert_hints;
  68 extern int    _af_debug_disable_blue_hints;
  69 extern void*  _af_debug_hints;
  70
  71 #else /* !AF_DEBUG */
  72
  73 #define AF_LOG( x )  do { } while ( 0 )        /* nothing */
  74
  75 #endif /* !AF_DEBUG */
  76
  77
  78   /*************************************************************************/
  79   /*************************************************************************/
  80   /*****                                                               *****/
  81   /*****                 U T I L I T Y   S T U F F                     *****/
  82   /*****                                                               *****/
  83   /*************************************************************************/
  84   /*************************************************************************/
  85
  86   typedef struct  AF_WidthRec_
  87   {
  88     FT_Pos  org;  /* original position/width in font units              */
  89     FT_Pos  cur;  /* current/scaled position/width in device sub-pixels */
  90     FT_Pos  fit;  /* current/fitted position/width in device sub-pixels */
  91
  92   } AF_WidthRec, *AF_Width;
  93
  94
  95   FT_LOCAL( void )
  96   af_sort_pos( FT_UInt  count,
  97                FT_Pos*  table );
  98
  99   FT_LOCAL( void )
 100   af_sort_widths( FT_UInt   count,
 101                   AF_Width  widths );
 102
 103
 104   /*************************************************************************/
 105   /*************************************************************************/
 106   /*****                                                               *****/
 107   /*****                   A N G L E   T Y P E S                       *****/
 108   /*****                                                               *****/
 109   /*************************************************************************/
 110   /*************************************************************************/
 111
 112   /*
 113    *  The auto-fitter doesn't need a very high angular accuracy;
 114    *  this allows us to speed up some computations considerably with a
 115    *  light Cordic algorithm (see afangles.c).
 116    */
 117
 118   typedef FT_Int  AF_Angle;
 119
 120
 121 #define AF_ANGLE_PI   256
 122 #define AF_ANGLE_2PI  ( AF_ANGLE_PI * 2 )
 123 #define AF_ANGLE_PI2  ( AF_ANGLE_PI / 2 )
 124 #define AF_ANGLE_PI4  ( AF_ANGLE_PI / 4 )
 125
 126
 127 #if 0
 128   /*
 129    *  compute the angle of a given 2-D vector
 130    */
 131   FT_LOCAL( AF_Angle )
 132   af_angle_atan( FT_Pos  dx,
 133                  FT_Pos  dy );
 134
 135
 136   /*
 137    *  compute `angle2 - angle1'; the result is always within
 138    *  the range [-AF_ANGLE_PI .. AF_ANGLE_PI - 1]
 139    */
 140   FT_LOCAL( AF_Angle )
 141   af_angle_diff( AF_Angle  angle1,
 142                  AF_Angle  angle2 );
 143 #endif /* 0 */
 144
 145
 146 #define AF_ANGLE_DIFF( result, angle1, angle2 ) \
 147   FT_BEGIN_STMNT                                \
 148     AF_Angle  _delta = (angle2) - (angle1);     \
 149                                                 \
 150                                                 \
 151     _delta %= AF_ANGLE_2PI;                     \
 152     if ( _delta < 0 )                           \
 153       _delta += AF_ANGLE_2PI;                   \
 154                                                 \
 155     if ( _delta > AF_ANGLE_PI )                 \
 156       _delta -= AF_ANGLE_2PI;                   \
 157                                                 \
 158     result = _delta;                            \
 159   FT_END_STMNT
 160
 161
 162   /*************************************************************************/
 163   /*************************************************************************/
 164   /*****                                                               *****/
 165   /*****                    O U T L I N E S                            *****/
 166   /*****                                                               *****/
 167   /*************************************************************************/
 168   /*************************************************************************/
 169
 170   /*  opaque handle to glyph-specific hints -- see `afhints.h' for more
 171    *  details
 172    */
 173   typedef struct AF_GlyphHintsRec_*  AF_GlyphHints;
 174
 175   /*  This structure is used to model an input glyph outline to
 176    *  the auto-hinter.  The latter will set the `hints' field
 177    *  depending on the glyph's script.
 178    */
 179   typedef struct  AF_OutlineRec_
 180   {
 181     FT_Face        face;
 182     FT_Outline     outline;
 183     FT_UInt        outline_resolution;
 184
 185     FT_Int         advance;
 186     FT_UInt        metrics_resolution;
 187
 188     AF_GlyphHints  hints;
 189
 190   } AF_OutlineRec;
 191
 192
 193   /*************************************************************************/
 194   /*************************************************************************/
 195   /*****                                                               *****/
 196   /*****                       S C A L E R S                           *****/
 197   /*****                                                               *****/
 198   /*************************************************************************/
 199   /*************************************************************************/
 200
 201   /*
 202    *  A scaler models the target pixel device that will receive the
 203    *  auto-hinted glyph image.
 204    */
 205
 206   typedef enum  AF_ScalerFlags_
 207   {
 208     AF_SCALER_FLAG_NO_HORIZONTAL = 1,  /* disable horizontal hinting */
 209     AF_SCALER_FLAG_NO_VERTICAL   = 2,  /* disable vertical hinting   */
 210     AF_SCALER_FLAG_NO_ADVANCE    = 4   /* disable advance hinting    */
 211
 212   } AF_ScalerFlags;
 213
 214
 215   typedef struct  AF_ScalerRec_
 216   {
 217     FT_Face         face;        /* source font face                        */
 218     FT_Fixed        x_scale;     /* from font units to 1/64th device pixels */
 219     FT_Fixed        y_scale;     /* from font units to 1/64th device pixels */
 220     FT_Pos          x_delta;     /* in 1/64th device pixels                 */
 221     FT_Pos          y_delta;     /* in 1/64th device pixels                 */
 222     FT_Render_Mode  render_mode; /* monochrome, anti-aliased, LCD, etc.     */
 223     FT_UInt32       flags;       /* additional control flags, see above     */
 224
 225   } AF_ScalerRec, *AF_Scaler;
 226
 227
 228 #define AF_SCALER_EQUAL_SCALES( a, b )      \
 229           ( (a)->x_scale == (b)->x_scale && \
 230             (a)->y_scale == (b)->y_scale && \
 231             (a)->x_delta == (b)->x_delta && \
 232             (a)->y_delta == (b)->y_delta )
 233
 234
 235   /*************************************************************************/
 236   /*************************************************************************/
 237   /*****                                                               *****/
 238   /*****                       S C R I P T S                           *****/
 239   /*****                                                               *****/
 240   /*************************************************************************/
 241   /*************************************************************************/
 242
 243   /*
 244    *  The list of know scripts.  Each different script corresponds to the
 245    *  following information:
 246    *
 247    *   - A set of Unicode ranges to test whether the face supports the
 248    *     script.
 249    *
 250    *   - A specific global analyzer that will compute global metrics
 251    *     specific to the script.
 252    *
 253    *   - A specific glyph analyzer that will compute segments and
 254    *     edges for each glyph covered by the script.
 255    *
 256    *   - A specific grid-fitting algorithm that will distort the
 257    *     scaled glyph outline according to the results of the glyph
 258    *     analyzer.
 259    *
 260    *  Note that a given analyzer and/or grid-fitting algorithm can be
 261    *  used by more than one script.
 262    */
 263
 264   typedef enum  AF_Script_
 265   {
 266     AF_SCRIPT_NONE  = 0,
 267     AF_SCRIPT_LATIN = 1,
 268     AF_SCRIPT_CJK   = 2,
 269     AF_SCRIPT_INDIC = 3,
 270 #ifdef FT_OPTION_AUTOFIT2
 271     AF_SCRIPT_LATIN2,
 272 #endif
 273
 274     /* add new scripts here.  Don't forget to update the list in */
 275     /* `afglobal.c'.                                             */
 276
 277     AF_SCRIPT_MAX   /* do not remove */
 278
 279   } AF_Script;
 280
 281
 282   typedef struct AF_ScriptClassRec_ const*  AF_ScriptClass;
 283
 284   typedef struct  AF_ScriptMetricsRec_
 285   {
 286     AF_ScriptClass  clazz;
 287     AF_ScalerRec    scaler;
 288     FT_Bool         digits_have_same_width;
 289
 290   } AF_ScriptMetricsRec, *AF_ScriptMetrics;
 291
 292
 293   /*  This function parses an FT_Face to compute global metrics for
 294    *  a specific script.
 295    */
 296   typedef FT_Error
 297   (*AF_Script_InitMetricsFunc)( AF_ScriptMetrics  metrics,
 298                                 FT_Face           face );
 299
 300   typedef void
 301   (*AF_Script_ScaleMetricsFunc)( AF_ScriptMetrics  metrics,
 302                                  AF_Scaler         scaler );
 303
 304   typedef void
 305   (*AF_Script_DoneMetricsFunc)( AF_ScriptMetrics  metrics );
 306
 307
 308   typedef FT_Error
 309   (*AF_Script_InitHintsFunc)( AF_GlyphHints     hints,
 310                               AF_ScriptMetrics  metrics );
 311
 312   typedef void
 313   (*AF_Script_ApplyHintsFunc)( AF_GlyphHints     hints,
 314                                FT_Outline*       outline,
 315                                AF_ScriptMetrics  metrics );
 316
 317
 318   typedef struct  AF_Script_UniRangeRec_
 319   {
 320     FT_UInt32  first;
 321     FT_UInt32  last;
 322
 323   } AF_Script_UniRangeRec;
 324
 325 #define AF_UNIRANGE_REC( a, b ) { (FT_UInt32)(a), (FT_UInt32)(b) }
 326
 327   typedef const AF_Script_UniRangeRec  *AF_Script_UniRange;
 328
 329
 330   typedef struct  AF_ScriptClassRec_
 331   {
 332     AF_Script                   script;
 333     AF_Script_UniRange          script_uni_ranges; /* last must be { 0, 0 } */
 334
 335     FT_Offset                   script_metrics_size;
 336     AF_Script_InitMetricsFunc   script_metrics_init;
 337     AF_Script_ScaleMetricsFunc  script_metrics_scale;
 338     AF_Script_DoneMetricsFunc   script_metrics_done;
 339
 340     AF_Script_InitHintsFunc     script_hints_init;
 341     AF_Script_ApplyHintsFunc    script_hints_apply;
 342
 343   } AF_ScriptClassRec;
 344
 345 /* Declare and define vtables for classes */
 346 #ifndef FT_CONFIG_OPTION_PIC
 347
 348 #define AF_DECLARE_SCRIPT_CLASS(script_class)                                \
 349   FT_CALLBACK_TABLE const AF_ScriptClassRec                                  \
 350   script_class;
 351
 352 #define AF_DEFINE_SCRIPT_CLASS(script_class, script_, ranges, m_size,        \
 353                                m_init, m_scale, m_done, h_init, h_apply)     \
 354   FT_CALLBACK_TABLE_DEF const AF_ScriptClassRec                              \
 355   script_class =                                                             \
 356   {                                                                          \
 357     script_,                                                                 \
 358     ranges,                                                                  \
 359                                                                              \
 360     m_size,                                                                  \
 361                                                                              \
 362     m_init,                                                                  \
 363     m_scale,                                                                 \
 364     m_done,                                                                  \
 365                                                                              \
 366     h_init,                                                                  \
 367     h_apply                                                                  \
 368   };
 369
 370 #else
 371
 372 #define AF_DECLARE_SCRIPT_CLASS(script_class)                                \
 373   FT_LOCAL(void)                                                             \
 374   FT_Init_Class_##script_class(AF_ScriptClassRec* ac);
 375
 376 #define AF_DEFINE_SCRIPT_CLASS(script_class, script_, ranges, m_size,        \
 377                                m_init, m_scale, m_done, h_init, h_apply)     \
 378   FT_LOCAL_DEF(void)                                                         \
 379   FT_Init_Class_##script_class(AF_ScriptClassRec* ac)                        \
 380   {                                                                          \
 381     ac->script                = script_;                                     \
 382     ac->script_uni_ranges     = ranges;                                      \
 383                                                                              \
 384     ac->script_metrics_size   = m_size;                                      \
 385                                                                              \
 386     ac->script_metrics_init   = m_init;                                      \
 387     ac->script_metrics_scale  = m_scale;                                     \
 388     ac->script_metrics_done   = m_done;                                      \
 389                                                                              \
 390     ac->script_hints_init     = h_init;                                      \
 391     ac->script_hints_apply    = h_apply;                                     \
 392   }
 393 #endif
 394
 395
 396 /* */
 397
 398 FT_END_HEADER
 399
 400 #endif /* __AFTYPES_H__ */
 401
 402
 403 /* END */